The Inactivation by Curcumin-Mediated Photosensitization of Botrytis cinerea Spores Isolated from Strawberry Fruits.

Photosensitization is a novel environmentally friendly technology with promising applications in the food industry to extend food shelf life. In this study, the natural food dye curcumin, when combined with visible light (430 nm), was shown to be an effective photosensitizer against the common phytopathogenic fungi Botrytis cinerea (the cause of grey mould). Production of the associated phytotoxic metabolites botrydial and dihydrobotrydial was measured by our newly developed and validated HRAM UPLC-MS/MS method, and was also shown to be reduced by this treatment. With a light dose of 120 J/cm2, the reduction in spore viability was directly proportional to curcumin concentrations, and the overall concentration of both botrydial and dihydrobotrydial also decreased with increasing curcumin concentration above 200 µM. With curcumin concentrations above 600 µM, the percentage reduction in fungal spores was close to 100%. When the dye concentration was increased to 800 µM, the spores were completely inactive and neither botrydial nor dihydrobotrydial could be detected. These results suggest that curcumin-mediated photosensitization is a potentially effective method to control B. cinerea spoilage, and also to reduce the formation of these phytotoxic botryane secondary metabolites.

Effect of solid-state fermentation on proximate composition, anti-nutritional factor, microbiological and functional properties of lupin flour.

The effects of solid-state fermentation (SSF) with Aspergillus sojae, Aspergillus ficuum and their co-cultures on proximate composition, anti-nutritional factor, microbiological and functional properties of lupin flour (LF) were investigated. Fibre fractions, in vitro enzyme protein digestion (IVPD), total phenolic contents, protein molecular distribution and colour attributes were also evaluated. Samples differed in their proximate composition except ash and fibre contents. The microbiological counts of the fermented LFs were generally higher (p < 0.05) than that of the unfermented LF. Phytic acid content and IVPD decreased (p < 0.05) in the fermented LFs. Also, the fermented LFs showed decreased (p < 0.05) water absorption capacity but increased swelling capacity. In addition, fermented LFs demonstrated reduction in colour attributes. Thus, the study indicated that SSF using Aspergillus sojae and Aspergillus ficuum can influence the physical, chemical and functional properties of LF. LF has great potentials in developing new nutritious food products and feed formulations when subjected to SSF.